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[texts]Character variability and a new synonym of Acerpenna pygmaea (Ephemeroptera: Baetidae) (Volume v. 109 1998)

Keywords: character variability in acerpenna
Downloads: 22
[texts]6. Morphological And Biochemical.full
Fusarium wilt is one of the devastating diseases of tobacco caused by Fusarium oxysporum which is a soil borne plant pathogen. Fourteen isolates were isolated from Hunsur, Piriyapatna belt 1 & 2 and H. D. Kote. These isolates exhibited morphological variations on PSA media. Further these isolates were subjected to SDS PAGE and variations were found prominent. The molecular weight of all protein bands ranged from 14.3 kDa to 97.4 kDa...
Keywords: Fusarium oxysporum; SDS PAGE; Variability; Carling Reaction
Downloads: 2
[texts]9. Agri Gentic Variability CH. SUSMITA
Micronutrient malnutrition resulting from dietary deficiency of iron (Fe), zinc (Zn) and other essential nutrients, is a wide spread food-related health problem globally. Diversified food and cultivars with elevated levels of nutrients provide most cost effective solution for this alarming problem. The success of an effective breeding programme and the genetic improvement of any crop species depend upon the nature of genetic variability present in the population...
Keywords: Malnutrition; Variability; Nutrients; Selection; Heritability; Genetic Advance
[texts]Seed vigor measurements and their use in predicting field establishment of grain pearl millet (Pennisetum Americanum) - Mwageni, Gallus Joseph.
This volume was digitized and made accessible online due to deterioration of the original print copy.
Keywords: Pearl millet--Field experiments; Seeds--Variability
Downloads: 29
[texts]50
 This paper presents a spin-transfer torque- magnetictunnel junction (STT-MTJ) based non-volatile 9-transistor(9T) SRAM cell. The cell achieves low power dissipation dueto its series connected MTJ elements and read buffer whichoffer stacking effect. The paper studies the impact of PVT(process, voltage, and temperature) variations on the designmetric of the SRAM cell such as write delay and compares theresults with non-volatile 8T SRAM cell (NV8T)...
Keywords: variability; SRAM; RSNM; WSNM; MTJ; hold power
Downloads: 7
[texts]6. Morphological And Biochemical.full
Fusarium wilt is one of the devastating diseases of tobacco caused by Fusarium oxysporum which is a soil borne plant pathogen. Fourteen isolates were isolated from Hunsur, Piriyapatna belt 1 & 2 and H. D. Kote. These isolates exhibited morphological variations on PSA media. Further these isolates were subjected to SDS PAGE and variations were found prominent. The molecular weight of all protein bands ranged from 14.3 kDa to 97.4 kDa...
Keywords: Fusarium oxysporum; SDS PAGE; Variability; Carling Reaction
Downloads: 23
[texts]6. Agri Genetic Uday G
Grain protein content in rice is an important nutritional parameter and development of quality rice with enhanced nutrition is very essential for eradication of malnutrition in the developing world. Evaluation of genetic variability is the source for any crop improvement programme, the success of which depends on sufficient genetic variability among genotypes permitting in effective selection. Genetic variability for many of the quantitative traits is enormously available in rice and variability...
Keywords: Variability; Total Grain Protein Content (TPG); Recombinant Inbred Line (RIL)
Downloads: 1
[texts]Genetic Variability in Barley (Hordeum vulgare (L.)) Landrace Collections from Southern Ethiopia - Shegaw Derbew, Elias Urage, Hussein Mohammed
Landraces are the major genetic resources of cultivated barley in Ethiopia. Two hundred seven accession and 18 releasedvarieties were laid out in 15by15 simple lattice design and were planted in 2008 main cropping season at Kokate. The objectives of thestudy were to conduct the morphological characterization and to determine the nature and degree of variability in morpho- agronomictraits of the barley landrace collections from southern Ethiopia...
Keywords: Hordeum vulgare; Landrace; Variability; Clustering; Morpho-agronomic characters
Downloads: 2
[texts]COLLISION WITH SODIUM ATOMS IN ONE OF THE TWO 3 P2 STATES - SEIWERT, R
ATTEMPTS ARE MADE TO CLARIFY MEASURING DISCREPANCIES IN THE STUDY OF TWO D LINES RADIATED INTO PURE SODIUM VAPOR, A SODIUM VAPOR AIR MIXTURE, AND A SODIUM POTASSIUM VAPOR MIXTURE. RESULTS SHOW THAT THE INTENSITY RATIOS OF THE TWO RESONANCE LINES IN FLUORESCENT LIGHT IS MARKEDLY INFLUENCED BY THE RADIATION DIFFUSION AND THAT THE MEASURED VALUES THEREFORE DEPEND ON THE GEOMETRY OF THE SYSTEM. IF THIS IS TAKEN INTO ACCOUNT, THE APPARENT CONTRADICTION BETWEEN OTHER EXPERIMENTAL STUDIES CAN BE EXPLAI...
Keywords: DIFFERENTIAL EQUATIONS; PROBLEM SOLVING; THEOREMS; OPERATORS (MATHEMATICS); VARIABILITY
Downloads: 71
[texts]Variation of the Solar He I 10830 A Line: 1977 - 1980 - Harvey, J. W
Daily measurements of the equivalent width of the 10830 A He I line integrated over the visible disk show: (1) an increase from about 32 to about 74 mA in the monthly mean values from the minimum to the maximum of the current solar cycle; (2) the monthly mean values are more smoothly varying than most other indices of solar activity; (3) rotation modulates the daily values in a highly variable manner with amplitudes as large as plus or minus 20%; (4) the apparent synodic rotation period is 29 da...
Keywords: SECULAR VARIATIONS; SOLAR DIAMETER; VARIABILITY; RADII; SOLAR CYCLES; SUN
Downloads: 59
[texts]Developmental changes in cortical processing as reflected by visually evoked potential variability - Street, Wilma Jeanne
Typescript
Keywords: Human information processing in children; Variability (Psychometrics); Visual evoked response
Downloads: 86
[movies]Part 2: Variability of Respirator Fit Test Panels - NIOSH Study Results - Tuesday, August 20, 2013
Tuesday, August 20, 2013 - Interactive webinar is to provide further opportunity to discuss the description and results of a NIOSH study assessing the fluctuation between bivariate panels used in respirator fit which was the topic of the July 23, 2013 webinar.
Keywords: NIOSH; NPPTL; Variability; Respirator; Fit Test Panels; bivariate panels
Downloads: 286
[texts]16. Applied Analysis Ramanappa - T. M. Ramanappa, K. Chandrashekara & D. Nuthan
Chickpea is the premier pulse crop of India grown on about 8.25 million ha. area with a production of 7.05 million tones, which accounts for 75% of the world chickpea production. In Karnataka, the area under chickpea is around 6.50 lakh ha. with a production of 3.1 lakh tonnes at an average productivity of 620kg/ha. However, the overall production and productivity of the country is much lower than the other countries...
Keywords: Chickpea Cicer arietinum L; Environmental Variability; Fertilizing Crops
Downloads: 16
[texts]GPS/Magnetometer Based Satellite Navigation and Attitude Determination - Deutschmann, Julie
In recent years algorithms were developed for orbit, attitude and angular-rate determination of Low Earth Orbiting (LEO) satellites. Those algorithms rely on measurements of magnetometers, which are standard, relatively inexpensive, sensors that are normally installed on every LEO satellite. Although magnetometers alone are sufficient for obtaining the desired information, the convergence of the algorithms to the correct values of the satellite orbital parameters, position, attitude and angular ...
Keywords: NONTHERMAL RADIATION; BLAZARS; PLASMA JETS; VARIABILITY; STELLAR FLARES; STRATIFICATION
Downloads: 156
[texts]Genetic Variability in Barley (Hordeum vulgare (L.)) Landrace Collections from Southern Ethiopia - Shegaw Derbew, Elias Urage, Hussein Mohammed
Landraces are the major genetic resources of cultivated barley in Ethiopia. Two hundred seven accession and 18 releasedvarieties were laid out in 15by15 simple lattice design and were planted in 2008 main cropping season at Kokate. The objectives of thestudy were to conduct the morphological characterization and to determine the nature and degree of variability in morpho- agronomictraits of the barley landrace collections from southern Ethiopia...
Keywords: Hordeum vulgare; Landrace; Variability; Clustering Morpho-agronomic characters
Downloads: 5
[texts]Nuevas exploraciones y posición taxonómica de Dorcadion tricolor Schramm 1910, Dorcadion albarium Escalera 1902, Dorcadion turdetanum Lauffer 1911 y Dorcadion bilbilitanum Escalera 1914, (Coleoptera, Cerambycidae). - Tomé, Mario
The discovery of new populations and the field work on the Dorcadion tricolor Schramm, 1910, Dorcadion albarium Escalera, 1902, Dorcadion turdetanum Lauffer, 1911 y Dorcadion bilbilitanum Escalera, 1914 allow a better understanding of their variability and geographical distribution. The study of new typical material, so far unknown, has been decisive to understand the morphologic connections with other taxa...
Keywords: Coleoptera; Cerambycidae; Dorcadion; Iberodorcadion; schrammianum; albarium; turdetanum; belbezei; variability; taxonomy
Downloads: 26
[texts]Variability of spectral tristimulus values (Volume 65A) - Nimeroff, Isadore
Journal of Research of the National Bureau of Standards
Keywords: Color-mixture data; spectral data; tristimulus values; variability
Downloads: 28
[texts]Performance Assessment of a Large Scale Pulsejet- Driven Ejector System - Paxson, Daniel E.
Unsteady thrust augmentation was measured on a large scale driver/ejector system. A 72 in. long, 6.5 in. diameter, 100 lb(sub f) pulsejet was tested with a series of straight, cylindrical ejectors of varying length, and diameter. A tapered ejector configuration of varying length was also tested. The objectives of the testing were to determine the dimensions of the ejectors which maximize thrust augmentation, and to compare the dimensions and augmentation levels so obtained with those of other, s...
Keywords: BRAIN; BAYES THEOREM; NEUROPHYSIOLOGY; NEUROLOGY; MENTAL PERFORMANCE; VARIABILITY; TASKS; INFERENCE
Downloads: 102
[texts]Short and long term variations in the solar constant - Schatten, K. H
Short and long term variations in the solar constant are examined theoretically. The variations observed by the Solar Maximum Mission, lasting several days and associated with the passage of sunspot groups, strikingly demonstrates the well known lack of a bright ring effect around sunspots. This suggests that sunspot magnetic fields do not simply block the heat flowing upward into the photosphere. Rather, it is suggested that gravitational draining occurs; this cools sunspots and transports down...
Keywords: PERIODIC VARIATIONS; SOLAR CONSTANT; VARIABILITY; CALIBRATING; NIMBUS 7 SATELLITE; PYROHELIOMETERS
Downloads: 71
[movies]Variability of Respirator Fit Test Panels - NIOSH Study Results - Tuesday, July 23, 2013
Tuesday, July 23, 2013 - Recording of interactive webinar is to provide a description and results of a recent NIOSH study to assess the fluctuation between bivariate panels used in respirator fit testing.
Keywords: NIOSH; NPPTL; webinar; Variability; Respirator; Fit Test Panels; bivariate panels
Downloads: 310
[texts]BSTJ 62: 9. November 1983: Performance of the Queueing Network Analyzer. (Whitt, W.)
Bell System Technical Journal, 62: 9. November 1983 pp 2817-2843. Performance of the Queueing Network Analyzer. (Whitt, W.)
Keywords: qna; node; arrival; approximations; simulation; nodes; variability; approximation; poisson; network; system technical; bell system; external arrival; variability parameters; expected waiting; waiting time; superposition arrival; arrival processes; arrival process; variability parameter
Downloads: 33
[texts]3. Agri IJASR BIOPHYSICAL AND CROP Isaac Newton 3
The study aimed to quantify the relative contributions of soil fertility factors (S), pests and diseases (P) and crop management practices (M) to highland banana (Musa spp. AAA-EA) yields under heterogeneous on-farm conditions. Soil status, nutrient levels, pests, crop management from 150 mats within close (CH), mid (MH) and remote (RH) distances of10 homesteads in Butare, Southwest Uganda were monitored from 2006-2008...
Keywords: Within-Farm Variability; Relative Distance; Yield Limitation; Constraint; Wealth Class; East African Highland Banana; Uganda
[texts]Stirling laboratory research engines - NON
No Abstract Available
Keywords: SOLAR CONSTANT; SOLAR CYCLES; SOLAR MAXIMUM MISSION; VARIABILITY; CLIMATOLOGY; RADIOMETERS; SUNSPOTS
Downloads: 116
[texts]The Detection of Circumnuclear X-Ray Emission from the Seyfert Galaxy NGC 3516 - George, I. M.
We present the first high-resolution, X-ray image of the circumnuclear regions of the Seyfert 1 galaxy NGC 3516, using the Chandra X-ray Observatory (CXO). All three of the CXO observations reported were performed with one of the two grating assemblies in place, and here we restrict our analysis to undispersed photons (i.e. those detected in the zeroth-order). A previously-unknown X-ray source is detected approximately 6 arcsec (1.1h(sub 75)(exp -1) kpc) NNE of the nucleus (position angle approx...
Keywords: ANNUAL VARIATIONS; SEA ICE; VARIABILITY; ICE REPORTING; SATELLITE OBSERVATION; ALGORITHMS; ARCTIC OCEAN; REGRESSION ANALYSIS
Downloads: 68
[texts]Small Mercury Ion Clock for On-board Spacecraft Navigation - Prestage, John D.
I.Small Ion Clock Approach and Heritage: a) No lasers, uwave cavities, cryogenics, atomic beams, etc. b) Ions are electrically shuttled between separate optical and microwave traps. II. Each trap is optimized for its task: quadrupole for optical state selection; multi-pole for microwave clock. a) Very good stability shown in USNO. Timescale running ''open loop.'' III. ''Open loop'' operation means no self-measurements of frequency offsets: (Zeeman, ion temperature,.....
Keywords: AEROSOLS; BIAS; HUMIDITY; CLOUDS (METEOROLOGY); MODIS (RADIOMETRY); CLIMATOLOGY; IMAGING SPECTROMETERS; OPTICAL THICKNESS; VARIABILITY; REJECTION
Downloads: 152
[texts]A Study of Direct and Cloud-Mediated Radiative Forcing of Climate Due to Aerosols - Yu, Shao-Ca
The Intergovernmental Panel on Climate Change (IPCC) has reported that in the southeastern US and eastern China, the general greenhouse warming due to anthropogenic gaseous emissions is dominated by the cooling effect of anthropogenic aerosols. To verify this model prediction in eastern China and southeastern US, we analyzed regional patterns of climate changes at 72 stations in eastern China during 1951- 94 (44 years), and at 52 stations in the southeastern US during 1949-94 (46 years) to detec...
Keywords: SATELLITE OBSERVATION; SEA ICE; ANTARCTIC REGIONS; ATMOSPHERIC MODELS; SEASONS; CLIMATE; SURFACE TEMPERATURE; TRENDS; VARIABILITY
Downloads: 122
[texts]Forces and Moments on Sphere-Cone Bodies in Newtonian Flow - Dickey, Robert R
The static longitudinal aerodynamic characteristics of a family of sphere-cone combinations (fineness ratios from 1.0 to 6.0) were computed by means of Newtonian impact theory. The effects of angle of attack, fineness ratio, and center-of-gravity location are shown. The results indicate that, with the center of gravity at or near the center of volume, the sphere-cone combinations are statically stable at trim points that provide low to moderate lift-drag ratios...
Keywords: ALGORITHMS; REFLECTANCE; VARIABILITY; CHLOROPHYLLS; FLUORESCENCE; UPWELLING WATER; ANTARCTIC OCEAN; COORDINATION; IMAGING SPECTROMETERS; LAUNCHING; REFINING
Downloads: 124
[texts]Exploration studies technical report. Volume 1: Mission and integrated systems - NON
The Office of Exploration (OEXP) at NASA Headquarters was tasked with defining and recommending alternatives for an early 1990's national decision on a focused program of human exploration of the solar system. The Mission Analysis and System Engineering (MASE) group, which is managed by the Exploration Studies Office at JSC, is responsible for coordinating the technical studies necessary for accomplishing such a task...
Keywords: ALGORITHMS; VARIABILITY; CALIBRATING; COMPUTER PROGRAMS; ENERGY SPECTRA; GAMMA RAY BURSTS; SPECTRUM ANALYSIS; MATRICES (MATHEMATICS); OCCULTATION; PULSARS
Downloads: 127
[texts]Improved Tensile Adhesion Specimens for High Strength Epoxy Systems in Aerospace Applications - Haddock, M. Reed
An improved tensile adhesion button has been designed and tested that results in higher measured tensile adhesion strength while providing increased capability for testing high strength epoxy adhesive systems. The best attributes of two well-established tensile button designs were combined and refined into an optimized tensile button. The most significant design change to the tensile button was to improve alignment of the bonded tensile button specimens during tensile testing by changing the int...
Keywords: VARIABILITY; GRID GENERATION (MATHEMATICS); SIMULATION; CLIMATE MODELS; SUMMER; STRETCHING; HEIGHT; DROUGHT
Downloads: 109
[texts]Functional Flight Test Report for Positive Systems' ADAR System 5500 Sensor SN8 Linear - Blonski, Slawomir
This report describes results of the functional flight test conducted with the Positive Systems' ADAR 5500 sensor system (serial number 8, linear configuration) near Winslow, Arizona on June 30 and July 1, 1999. The in-flight test is one component of the NASA Scientific Data Purchase (SDP) Validation and Verification (V&V) process. It allows to measure characteristics of the entire sensor system affected by both performance of the sensor during a flight and post-flight image processing...
Keywords: FORECASTING; MOISTURE CONTENT; OSCILLATIONS; PREDICTIONS; SIMULATION; WEATHER; VARIABILITY; TROPICAL REGIONS; HEAT TRANSFER; ARCTIC REGIONS; HEATING; HINDCASTING
Downloads: 95
[texts]Mount Rainier active cascade volcano - NON
Mount Rainier is one of about two dozen active or recently active volcanoes in the Cascade Range, an arc of volcanoes in the northwestern United States and Canada. The volcano is located about 35 kilometers southeast of the Seattle-Tacoma metropolitan area, which has a population of more than 2.5 million. This metropolitan area is the high technology industrial center of the Pacific Northwest and one of the commercial aircraft manufacturing centers of the United States...
Keywords: COLOR; MORPHOLOGY; VIABILITY; GERMINATION; IMAGE ENHANCEMENT; PHYTOTRONS; RADIOGRAPHY; SEEDS; TREES; VARIABILITY; IMAGING TECHNIQUES
Downloads: 75
[texts]Automated Environment Generation for Software Model Checking - Tkachuk, Oksana
A key problem in model checking open systems is environment modeling (i.e., representing the behavior of the execution context of the system under analysis). Software systems are fundamentally open since their behavior is dependent on patterns of invocation of system components and values defined outside the system but referenced within the system. Whether reasoning about the behavior of whole programs or about program components, an abstract model of the environment can be essential in enabling...
Keywords: THREE DIMENSIONAL MODELS; VARIABILITY; ANNUAL VARIATIONS; TRANSPORT THEORY; TROPICAL REGIONS; DATA CORRELATION; SENSITIVITY; NONUNIFORMITY; WIND DIRECTION
Downloads: 88
[texts]Mineralogy of the Martian Surface: Crustal Composition to Surface Processes - Mustard, John F
The main results have been published in the refereed literature, and thus this report serves mainly to summarize the main findings and indicate where the detailed papers may be found. Reflectance spectroscopy has been an important tool for determining the mineralogic makeup of the near surface materials on Mars. Analysis of the spectral properties of the surface have demonstrated that these attributes are heterogeneous from the coarse spatial but high spectral resolution spectra obtained with te...
Keywords: ACTIVE GALACTIC NUCLEI; BLAZARS; GAMMA RAYS; MARKARIAN GALAXIES; VARIABILITY; GAMMA RAY TELESCOPES; GAMMA RAY OBSERVATORY
Downloads: 86
[texts]Solar Energetic Particles and Space Weather - Reames, Donald V.
The solar energetic particles (SEPs) of consequence to space weather are accelerated at shock waves driven out from the Sun by fast coronal mass ejections (CMEs). In the large events, these great shocks fill half of the heliosphere. SEP intensity profiles change appearance with longitude. Events with significant intensities of greater than ten MeV protons occur at an average rate of approx. 13 per year near solar maximum and several events with high intensities of > 100 McV protons occur each de...
Keywords: ALGORITHMS; MAXIMUM LIKELIHOOD ESTIMATES; QUALITY CONTROL; STATISTICAL TESTS; MATHEMATICAL MODELS; ASSIMILATION; COVARIANCE; VARIABILITY; STORMS
Downloads: 91
[texts]Raman Study of Uncoated and p-BN/SiC-Coated Hi-Nicalon Reinforced Celsian Matrix Composites - Gouadec, Gwenael
Band shifts on Raman spectra were used to assess, at a microscopic scale, the residual strain existing in Hi-Nicalon fibers reinforcing celsian matrix composites. Uncoated as well as p-BN/SiC- and p-B(Si)N/SiC-coated Hi-Nicalon fibers were used as the reinforcements. We unambiguously conclude that the fibers are in a state of compressive residual stress. Quantitative determination of the residual stress was made possible by taking into account the heating induced by laser probing and by using a ...
Keywords: FORESTS; GROUND TESTS; HYDROLOGY; SNOW; SNOW COVER; AIR LAND INTERACTIONS; REMOTE SENSING; SURVEYS; VARIABILITY
Downloads: 81
[texts]Optics-Only Calibration of a Neural-Net Based Optical NDE Method for Structural Health Monitoring - Decker, Arthur J
A calibration process is presented that uses optical measurements alone to calibrate a neural-net based NDE method. The method itself detects small changes in the vibration mode shapes of structures. The optics-only calibration process confirms previous work that the sensitivity to vibration-amplitude changes can be as small as 10 nanometers. A more practical value in an NDE service laboratory is shown to be 50 nanometers...
Keywords: ASSIMILATION; TROPOPAUSE; DISTRIBUTION FUNCTIONS; METHANE; PIPES (TUBES); PROBABILITY THEORY; VARIABILITY; VORTICES; UNCERTAIN SYSTEMS; TROPICAL REGIONS
Downloads: 61
[texts]Keeping a Spacecraft on the Sun-Earth Line - Roithmayr, Carlos M.
Measurements of Earth's atmosphere as it occults sunlight can be obtained advantageously from a spacecraft placed in the proximity of the Sun-Earth Lagrange point L2. Maintaining the condition of continuous solar occultation by all parts of the atmospheric disk requires that the displacement of the spacecraft perpendicular to the Sun-Earth line remains less than 200 km. However, the gravitational force exerted by the Earth's moon must be negated by propulsion in order to meet this rather tight c...
Keywords: ALGORITHMS; MONKEYS; EVOKED RESPONSE (PSYCHOPHYSIOLOGY); BIOELECTRIC POTENTIAL; MAGNETIC FIELDS; ELECTRIC FIELDS; VARIABILITY; SIMULATION; ROBUSTNESS (MATHEMATICS); NEURONS
Downloads: 64
[texts]Software Engineering Laboratory Series: Proceedings of the Twenty-Second Annual Software Engineering Workshop - NON
The Software Engineering Laboratory (SEL) is an organization sponsored by NASA/GSFC and created to investigate the effectiveness of software engineering technologies when applied to the development of application software. The activities, findings, and recommendations of the SEL are recorded in the Software Engineering Laboratory Series, a continuing series of reports that includes this document.
Keywords: COMPUTER PROGRAMS; ICE FORMATION; VARIABILITY; DATA BASES; ROBUSTNESS (MATHEMATICS); WEATHER; SPACING; SHAPES
Downloads: 329
[texts]Exercise Countermeasures for Bone Loss During Space Flight: A Method for the Study of Ground Reaction Forces and Their Implications for Bone Strain - Peterman, M.
The human zero-gravity locomotion simulator and the cadaver simulator offer a powerful combination for the study of the implications of exercise for maintaining bone quality during space flight. Such studies, when compared with controlled in-flight exercise programs, could help in the identification of a strain threshold for the prevention of bone loss during space flight.
Keywords: VARIABILITY; MODELS; EARTH SURFACE; SURFACE PROPERTIES; TOPOGRAPHY; DRAINAGE; SOIL MOISTURE; ATMOSPHERIC GENERAL CIRCULATION MODELS; CLIMATOLOGY
Downloads: 123
[texts]Autonomy Software: V&V Challenges and Characteristics - Schumann, Johann
The successful operation of unmanned air vehicles requires software with a high degree of autonomy. Only if high level functions can be carried out without human control and intervention, complex missions in a changing and potentially unknown environment can be carried out successfully. Autonomy software is highly mission and safety critical: failures, caused by flaws in the software cannot only jeopardize the mission, but could also endanger human life (e.g., a crash of an UAV in a densely popu...
Keywords: BLACK HOLES (ASTRONOMY); VARIABILITY; ENERGY SPECTRA; COMPTON EFFECT; POWER SPECTRA; FOURIER ANALYSIS; CORONAS; RECLAMATION; LOW FREQUENCIES
Downloads: 95
[texts]Converting a CO2 atmosphere to a high-purity O2 supply - NON
A CO2 atmosphere or any other oxygen bearing gas is converted to a high-purity O2 supply by in-letting a flow of CO2 from the atmosphere into a closed container, which is equipped with a means for creating a glow discharge or other method for dissociation in proximity to a permeable silver membrane kept at a temperature between about 400 and 800 C. A glow discharge is created to dissociate the CO2 to form a partial pressure of atomic and molecular oxygen...
Keywords: CLIMATE; CLIMATE CHANGE; METEOROLOGICAL PARAMETERS; PREDICTION ANALYSIS TECHNIQUES; WEATHER FORECASTING; METEOROLOGICAL CHARTS; VARIABILITY
Downloads: 76
[texts]Assessing MMOD Impacts on Seal Performance - deGroh, Henry C., III
The elastomer seal needed to seal in cabin air when NASA s Crew Exploration Vehicle is docked is exposed to space prior to docking. While open to space, the seal might be hit by orbital debris or meteoroids. The likelihood of damage of this type depends on the size of the particle. Our campaign is designed to find the smallest particle that will cause seal failure resulting in loss of mission. We will then be able to estimate environmental risks to the seal...
Keywords: MARS MISSIONS; INFLATABLE STRUCTURES; DESCENT; LANDING SITES; DEPLOYMENT; MARS SURFACE; FLIGHT MECHANICS; TRADEOFFS; VARIABILITY; SUPPORT SYSTEMS
Downloads: 128
[texts]Differential equations of the equilibrium states of thin elastic shells in the postcritical stage - Alumyae, N. A
No Abstract Available
Keywords: DENSITY (MASS/VOLUME); GAS EXPLOSIONS; NONLINEARITY; VARIABILITY; ONE DIMENSIONAL FLOW; SHOCK WAVES; UNSTEADY FLOW; WAVE PROPAGATION
Downloads: 87
[texts]Chronology of KSC and KSC Related Events for 2005 - Liston, Elaine E
This document is intended to serve as a record of KSC events and is a reference source for historians and other researchers. Arrangement is by day and month and individual articles are attributed to published sources. Materials were researched and described by the KSC Library .Archivist for KSC Library Services Contractor, InDyne, Inc.
Keywords: SEA ICE; SATELLITE OBSERVATION; CLIMATE MODELS; SOUTHERN HEMISPHERE; NORTHERN HEMISPHERE; VARIABILITY; TRENDS; SIMULATION
Downloads: 270
[texts]A Method for Calculating Strain Energy Release Rates in Preliminary Design of Composite Skin/Stringer Debonding Under Multi-Axial Loading - Krueger, Ronald
Three simple procedures were developed to determine strain energy release rates, G, in composite skin/stringer specimens for various combinations of unaxial and biaxial (in-plane/out-of-plane) loading conditions. These procedures may be used for parametric design studies in such a way that only a few finite element computations will be necessary for a study of many load combinations. The results were compared with mixed mode strain energy release rates calculated directly from nonlinear two-dime...
Keywords: CLIMATE CHANGE; CLIMATE; VARIABILITY; CLIMATE MODELS; CLIMATOLOGY; EL NINO; SOUTHERN OSCILLATION
Downloads: 107
[texts]Report to Congress on the restructuring of the Earth Observing System - NON
Contents: (1) The Science Objectives of EOS; (2) New Spacecraft Configurations; (3) The Impact of the Restructured EOS on Understanding the Climate; (4) The Impact of EOS on Adaptation and Mitigation Strategies; (5) EOS Data and Information System; (6) Interdisciplinary Investigations; (7) Missions in Advance of EOS; (8) The Role of the Departments of Energy and Defense; (9) Summary of the Mission to Planet Earth; and (10) Funding Requirement.
Keywords: HOMODYNE RECEPTION; INFRARED RADAR; MOUNTAINS; SIGNAL PROCESSING; STATISTICAL ANALYSIS; SIGNAL ANALYZERS; VARIABILITY
Downloads: 95
[texts]Magnetospheric Substorms and Tail Dynamics - Hughes, W. Jeffre
This grant funded several studies of magnetospheric substorms and their effect on the dynamics of the earth's geomagnetic tail. We completed an extensive study of plasmoids, plasma/magnetic field structures that travel rapidly down the tail, using data from the ISEE 3 and IMP 8 spacecraft. This study formed the PhD thesis of Mark Moldwin. We found that magnetically plasmoids are better described as flux-ropes (twisted magnetic flux tubes) rather than plasma bubbles, as had been generally regarde...
Keywords: CLOUDS (METEOROLOGY); ACTIVE GALACTIC NUCLEI; DENSITY (MASS/VOLUME); ATMOSPHERIC MODELS; VARIABILITY; SPECTRA; SEYFERT GALAXIES
Downloads: 82
[texts]A Regularized Neural Net Approach for Retrieval of Atmospheric and Surface Temperatures with the IASI Instrument - Aires, F.
Abstract In this paper, a fast atmospheric and surface temperature retrieval algorithm is developed for the high resolution Infrared Atmospheric Sounding Interferometer (IASI) space-borne instrument. This algorithm is constructed on the basis of a neural network technique that has been regularized by introduction of a priori information. The performance of the resulting fast and accurate inverse radiative transfer model is presented for a large divE:rsified dataset of radiosonde atmospheres incl...
Keywords: GEOPHYSICS; ROTATION; TIME SERIES ANALYSIS; PRINCIPAL COMPONENTS ANALYSIS; DECOMPOSITION; DATA SIMULATION; STATISTICAL ANALYSIS; VARIABILITY
Downloads: 84
[texts]Rupture behavior of elastomers- effect of statistical variability and crosslink density - Fedors, R. F.
Rupture behavior of elastomers - effect of variance on failure envelope resolution and effect of crosslink density on curve shape and location
Keywords: CROSSLINKING; ELASTOMER; FAILURE; RUPTURE; VARIANCE; ELASTOMERS; FAILURE; POSITION (LOCATION); RUPTURING; SHAPES; VARIABILITY; VARIANCE; CROSS LINKING
Downloads: 71
[texts]Spectroscopic Diagnostics and an Arc Jet Heated Air Plasma - Mack, Larry Howard, Jr
Spectral radiation measurements were made in the range of 200 to 900 nm across a section of the plenum of an arc jet wind tunnel using a series of optical fibers. The spectra contained line radiation from Oxygen and Nitrogen atoms and molecular radiation from N2(), N2, and NO. Abel inversion technique is used to obtain radial distribution of the spectra. The analysis yielded radial profiles of the electronic excitation, vibrational and rotational temperatures of the flow field...
Keywords: O STARS; B STARS; STELLAR ROTATION; ULTRAVIOLET SPECTRA; SPACEBORNE ASTRONOMY; IUE; ULTRAVIOLET SPECTROSCOPY; VARIABILITY; STELLAR WINDS
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